Drill collar reamer



A 1937. c. 1.. SKINNER 2,088,770

DRILL COLLAR REAMER Filed Dec. 2, 1956 I Patented Aug. 3, 1937 aosam mun. com seam Clarence Skinner, Frlendswood. Ten, assignor or fifty-one per cent to S. I. Timber-1y. Houston, Tex.

. Application December 2, 1936, Serial No. 113,893

11 Claims.

The present invention relates to drilling apparatus for oil wells,-and has for an object to provide a reamer adapted for use in connection with and above a drill bit for maintaining the size of the drill opening of the same diameter as cut by the bit so that the bit with its radiating blades may be readily withdrawn after the cutting operation, and the drilled hole will be ready to receive a well casing or tubing without the necessity of the usual additional and separate reaming operation. In accomplishing this object of the invention there is a great saving in time and expense to the driller and contractor in the sinking of wells, as the usual subsequent reaming out of the drilled hole is a very costly and time consuming operation but has been necessary heretofore before sinking the usual well casing.

Another object of the invention is to provide a reamer which embodies a drill collar construction and which carries, detachably, a plurality of radiating reamer blades substantially the radial length or diameter of the bit and its blades so as to work against the side of the drill opening above the bit and thus followthe bit to maintain the opening of uniform diameter and in straight axial line, and to thus prevent crooked holes.

The invention also embodies reamer blades which are beveled or otherwise constructed at opposite ends to facilitate their lengthwise move- 0 ment in the drilled hole and prevent the catching of the blades in the earth and other materials forming the wall of thehole as thettool is raised and lowered in the well hole, and to construct the reamer blades of triangular, or other suitable,

35 cross-sectional shape to provide a broad dove-tail base and to correspondingly recess the drill collar to rigidly and ably support the blades for operation simultaneously with the operation of the drill. I

The invention also provides a novel construction of drill collar and' reamer blade so that the latter are detachably and yieldably held upon the drill collar, and the parts are maintained in assembled position merely by the positioning of the 45 usual coupling employed between the drill collarand the drill stem.

With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed out 50 in the claims appended hereto.

In the drawing, wherein like eral views.

Figure 1 is a fragmentary longitudinal section 55 taken through a portion of a drilling apparatus,

symbols refer; to like or corresponding parts throughout the sev- Figure 4 is a detail perspective view of one of n the reamer blades.

Referring now to the drawing, l0 designates a drill or hit of any suitable construction and which has radiating drill blades I I in the usual manner. The drill bit I0 is provided, in the present instance, with an externally threaded upwardly tapering shank l2 which detachably screws into the lower end of a drill collar l3, the latter having the usual bore or opening l3 axially thereof for communication at its lower end with the bit.

The upper end of the drill collar i3 is recessed and threaded for receiving the depending threaded shank M of a coupling member l5 which is adapted, in the usual manner, for attachment to a drill stem which extends to the surface of the ground for operation of the apparatus.

According to the present invention, advantage is taken of the drill collar l3 located immediately above the-drill bit l0, and the drill collar i3 is provided with a plurality of radially extending reamer blades l6 which extend lengthwise of the collar l3 so as to be closely associated with the drill bit [0 and its blades H for maintaining the diameter of the drill hole uniform. By means of this construction the reamer blades l6 operate against the walls of the opening and facilitate the removal as well as the normal operation of the drill bit.

Each blade l6 of the reamer is shown in the present instance as of substantially triangular shape in cross section to provide a dove-tall in net or base portion I! which slidably fits in a correspondingly shaped slot l8 provided in the outer side wall of the, drill collar l3. tail base l1 and the slot l8 are preferably stepped to provide an intermediate dove-tailbase locking shoulder l! and a backwardly extending bracing portion ll for the blade. This construction notonly increases the anchorage and the contacting base surface of the blade IE to and against the drill collar l3, but also holds the blade against canting andlateral strains tending to shear off the bladelt at the-surface of the The dOVesuitable cushioning and supporting elements, are mounted in the lower ends of the slots l8, and the slots are provided with bottom walls 20 upon tom walls 20 are spaced a short distance above the lower end of the sleeve ii. The slots I8 are of suitable depth to receive asubstantial por-' tion of the dovetail inner ends of the reamer blades l6 so as to afford a firm and reliable support for the same, and the slots l8 open upwardly through the upper end of the, drill collar l3. The 6 coupling I is provided, around the depending shank H, with an annular downwardly facing 25 shoulder 2| which extends outwardly over the upper ends of the slots 18 and abuts 'the upper ends of the reamer blades iii to force the same downwardly in the slots 7 l8, and against the springs l9 when employed. The springs l9 are 30 thus compressed sufliciently to yieldingly hold the reamer bladeslfi up against the shoulder 2| of the coupling l5 and to thus hold the reamer blades yieldingly upon the collar l3.

The upper and lowerends of the blades iii are 3 beveled or cut away as at l6 to provide cam edges for the blades to prevent the same from,

catching in the earth or other material forming the wall of the drilled hole. These cam edges l6 thus facilitate the raising and lowering of 40 the combined drill bit and reamer without damage to the blades l6 and other parts of the tool.

It is apparent that when the drill collar is raised and .tumed the blades l6 eflect a cutting action upon the inner wall of the opening and, as

45 the reamer blades l6 extend outwardly a distance substantially equal to the distance of the drill or bit blades II, the drill or bit may be readily raised or withdrawn through the opening,

and the opening is reamed to the desired finished 50 size to receive the well casing without the usual and separate reaming operation. The springs l9 not only yieldingly hold the blades IS in position against the shoulder 2| but also serve as yielding or cushioning elements to absorb longi- 55 tudinal shock imposed upon the reamer blades during the lifting and cutting action.

Another feature of the springs I9 is that when it is desired to substitute, interchange or remove the reamer blades IS with respect to the drill collar I 3, the coupling member I5 is unscrewed from the upper end of the drill collar and the springs l 9 are adapted to slidably raise the reamer blades iii in their slots l8 for not only loosen- 5 ing the reamer blades in their slots but to also facilitate the removal of the reamer blades when such is desired. When the springs H) are not used the blades l6 and the slots l8 may be otherwise constructed as to length to hold the blades 7 ii on the collar l3 between the drill bit in and the stemcoupling l5.

In some instances the reamer blades l6 may stick and offer resistance to removal. To admit application of impact upon the reamerblades 75 it without damage thereto, each-reamer blade which the springs l9 are supported. Thesebotmay be provided with a depression 22 providing a shoulder against which a chisel or other suitable tool may be used to transmit the blows of a hammer or the like for dislodging the reamer blades l6 from the drill collar.

It is readily seen that in assembling the reamer upon the drill or hit ill, the drill collar I3 is connected to the bit in any suitable and well known manner, such as by the threaded shank l2 shown in the present instance. The reamer blades iii are now slid downwardly in their slots l8 and are brought into contact with the springs 9. The coupling member I5 is now connected to the drill collar. In the act of screwing down the coupling l5 upon the drill collar, the annula'r shoulder 2| of the coupling engages the upper ends of the reamer blades l6 and forces the same downwardly in their slots l8 against the tension of the springs IS. The reamer blades I6 are thus held securely in the drill collar and at the same time are permitted to yield when the drill collar is raised and should the reamer blades I6 meet'obstructions.

It is important that the reamer blades l6 be substantially of the same diameter as that of the drill bit blades II as one of the important objects or features of the reamer blades I6 is to.

remount or maintain the drill opening of the same diameter as it was cut by the drill or bit blades ll so that the drill or bit may be readily raised upwardly through the opening when desired.

It will be noted that the device is relatively simple, adds but few extra parts to the drilling apparatus and does not interfere with the ordinary or usual drill or coupling connections to the opposite ends of the drill collar, nor does it interfere with any of the structural features of the drill collar, such as the central bore l4.

It is obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claims:

What is claimed is:

1. In drilling apparatus, the combination of a drill bit, a drill collar connected to the bit provided with a plurality of longitudinal slots open at the upper ends thereof, and a drill stem coupling connected to the upper end of the collar and closing the upper ends of said slots, a plurality of reamer blades secured to said drill collar in said slots and extending radially therefrom a distance equal substantially to the radial length of the drill bit blades for maintaining the wall of the opening of the diameter cut by the drill bit, said blades having a length less than the length of said slots, and a spring in each slot engaging against the end of a blade to yieldably maintain said blade against said coupling.

2. In drilling apparatus, a drill bit, a drill collar connected to said bit and provided in its sides with longitudinal dovetail slots opening through the upper end thereof. and having bottom walls spaced from said drill bit, a coupling member detachably connected to the upper end of the drill collar and having a downwardly facing shoulder overhanging said slots, springs mounted in the lower ends of said slots, and reamer blades having dovetail inner edges slidably engaging in said slots and hearing at their upper ends against said shoulder of the coupling membet to hold said springs under compression and maintain the reamer blades yieldlngly in the drill collar.

3. In drilling apparatus, a drill collar adapted to carry a drill hit upon its lower end and provided in its outer sides with longitudinal slots of dovetail cross-section opening through the upper end of the drill collar and having bottom walls spaced from the lower end of the drill collar, coil springs seated on said bottom walls in the slots of the drill collar, and a plurality of reamer blades. having inner edges of dovetail cross-section slidably engaging in said slots and seated against said springs at their lower ends, said drill collar adapted to receive a coupling on its upper end and said blades adapted to bear against said coupling for holding the blades against said springs.

4. Drilling apparatus, comprising a drill bit having boring blades, a drill collar connected to the drill bit, a coupling member detachably connected to the upper end of the drill collar, said drill collar having longitudinal slots in its sides,

. opening through the upper end of the drill collar against the lower end of said coupling member, said slots having bottom walls spaced from the lower end of the collar, radial reamer blades fitting in said slots with their upper ends against the lower end of the coupling member, and cushioning members mounted in the lower ends of said slots against the lower ends of the blades to yieldingly hold the same upwardly in the slots,

said slots and the inner edges of said blades being of dovetail cross-section to hold the blades to the drill collar, said blades extending outwardly a distance substantially equal to the radial extension of the drill bit blades.

5. In well drilling apparatus, a drill collar adapted to carry a drlll'bit on its lower end and adapted for connection at its upper end to a drill stem, said drill collar having longitudinal exterior slots of substantially dovetail cross-section opening through the upper 'end of the collar, and a plurality of reamer blades having inner base portions of substantially dovetail cross-section adapted to slidably lit in said slots of the'collar, said blades adapted to engage at their upper ends against a drill stem when the collar is mounted thereon for holding the blades to the collar, said blades being of substantially triangular configuration in cross section with alrelatively short forward side and a relatively long'rear side, said rear side substantially merging with the surface of said collar.

6. In well drilling apparatus, a drill collar adapted to be coupled between a drill stem and a boring bit, said drill collar having longitudinal slots in its outer sides opening through one end thereof, and reamer' blades substantially triangular in cross-section having base portions fitting in said slots of the collar, said slots and said base portions of the blades being substantially dovetail in cross-section with. intermediate stepped dovetail shoulders therein to increase the anchorage and seating faces of the blades, said blades having relatively short front faces inclined at a slight angle to the radii of the collar and having outer beveled cutting edges and prolonged bracing sides extending from the cutting edges backwardly to the base portions of the blades for supporting the latter on the collar.

7. As a new article of manufacture. a drill collar adapted to be connected to and interposed between a bit member and a stem member, said collar having longitudinal keyways in the exterior thereof opening through at least one end, reamer blades provided with key portions slidably engaging in said-keyways and having a length less than the length of said keyways, said blades being removably maintained in said keyways when said collar is coupled to said members, and a spring in each keyway engaging against the adjacent end of a blade.

8'. As a new article of manufacture, a drill collar adapted to be connected to and interposed between a bit member and a stem member, said collar having exterior diameters at each end substantially coincident with the exterior diameters of said members and provided with longitudinal keyways opening through one end thereof, and triangular blades provided with key portions engaging in said keyways, said blades having a relatively short forward side and a relatively long rear side merging with the surface of said collar, the open ends of said keyways being closed by the adjacent end of one oi; said members to thereby removably maintain said blades in said keyways.

9. In well drilling apparatus, the combination of a drill collar comprising a body having longitudinal keyways opening through an end thereof, reamer blades having key portions engaging in said keyways and having a length less than the length of said keyways, a member threaded. onto said one end and having the adjacent end thereof overlying the ends of said keyways to thereby removably secure said blades in said keyways, and a spring in each keyway engaging against the adjacent end of a blade.

10. In well drilling apparatus, the combination of a drill collar comprising a body having longitudinal keyways opening through an end thereof, reamer blades having key portions slidably engaging in saidkeyways and having a length less than the length of said keyways, a member 7 threaded onto said one end and having the adjacent end thereof overlying the open ends of said keyways, and a spring in each keyway engaging against the adjacent end of a blade, each blade being substantially triangular in configuration and having a relatively short front side and a relatively long rear side.

11. In a drill collar reamer, a plurality of reamer blades, each blade comprising a member substantially triangular in cross section and a key carried by one side of said member, said memher being so disposed with respect to said key that the median line from the apex thereof will be disposed on an oblique angle to the median line of the key.

CLARENCE L. SKINNER. 

